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    GSM4K SIM installation guide

    The GSM4K is the intercom most UK gate engineers cut their teeth on. It's a modular audio panel from the Videx 4000 series: a GSM PRO module, up to 50 call buttons, and an antenna, calling out over the 2G network to any phone you program in. Each button can dial four numbers in sequence, so an unanswered call diverts rather than dies.

    Which SIM does the Videx GSM4K take?

    A standard size SIM (2FF) — the big one. Micro and nano SIMs will not fit without an adapter, and adapters cause more intercom callbacks than any other single item. Use a proper standard SIM.

    The SIM isn't supplied with the panel and must be registered with the network before it goes anywhere near the intercom.

    Which network?

    The GSM4K only works where its network has signal at the gate, not at the house. Videx themselves recommend surveying signal at the antenna position before choosing a provider. A multi-network SIM sidesteps the survey lottery by connecting to the strongest available network, and if coverage shifts after a mast change, it moves with it.

    If you're on a pay-monthly SIM, set a spend cap with the provider. A fault that dials out repeatedly can build an ugly bill.

    Fitting the SIM

    For the installing engineer, with the panel powered down:

    1. Find the SIM holder on the back of the GSM module, under the SMA antenna connection.
    2. Slide the holder left until it clicks, then hinge it open.
    3. Sit the SIM in the tray — it only fits one way.
    4. Fold the holder down and slide it right until it clicks home.

    First power-up

    Power up and leave it alone for about 30 seconds. You'll hear two short beeps, a pause, then single beeps as it initialises. Don't send SMS commands or press buttons while the busy LED is flashing. When it stops, make a test call from button 1.

    If it won't connect

    • No signal bars on a test call: move the antenna, not the panel. Height helps.
    • SMS commands ignored: check the SIM has an SMS service centre number stored — put it in a phone to check.
    • Registered but calls fail: confirm the button has a number programmed and the SIM has credit.

    FAQ

    Will the GSM4K work after the 2G switch-off? The 2G version depends on 2G remaining live in your area. UK networks are sunsetting 2G over the coming years. For new installs, fit the GSM4K/4G instead.

    Does Videx supply the SIM? No. The SIM is always supplied separately.

    Can I use any network? Any UK network with 2G coverage at the gate. A multi-network SIM removes the need to guess which that is.

    Keep your Videx GSM4K online.

    LynixSIM multi-network SIMs connect to the strongest UK signal (EE, O2, Vodafone, Three) — no single-network dropouts, no contracts, built for intercoms and gate systems.

    Get your SIM

    Full Videx GSM4K manual

    For wiring diagrams, programming syntax and full commissioning notes, download the manufacturer's manual we host.

    Open the GSM4K manual page
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